Limestone is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of CaCO3. Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as the accumulation of corals and shells in the sea, have likely been more important for the last 540 million years. Limestone often contains fossils which provide scientists with information on ancient environments and on the evolution of life.
Calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (CaCO3). It is a very common mineral, particularly as a component of limestone. Calcite defines hardness 3 on the Mohs scale of mineral hardness, based on scratch hardness comparison. Large calcite crystals are used in optical equipment, and limestone composed mostly of calcite has numerous uses.
Calcium carbonate is a chemical compound with the chemical formula CaCO3. It is a common substance found in rocks as the minerals calcite and aragonite and is the main component of eggshells, gastropod shells, shellfish skeletons and pearls. Things containing much calcium carbonate or resembling it are described as calcareous. Calcium carbonate is the active ingredient in agricultural lime and is created when calcium ions in hard water react with carbonate ions to create limescale. It has medical use as a calcium supplement or as an antacid, but excessive consumption can be hazardous and cause hypercalcemia and digestive issues.
Vaterite is a mineral, a polymorph of calcium carbonate (CaCO3). It was named after the German mineralogist Heinrich Vater. It is also known as mu-calcium carbonate (μ-CaCO3). Vaterite belongs to the hexagonal crystal system, whereas calcite is trigonal and aragonite is orthorhombic.
Saxifraga is the largest genus in the family Saxifragaceae, containing about 465 species of holarctic perennial plants, known as saxifrages or rockfoils. The Latin word saxifraga means literally "stone-breaker", from Latin saxum + frangere. It is usually thought to indicate a medicinal use for treatment of urinary calculi, rather than breaking rocks apart.
Roridula is a genus of evergreen, insect-trapping shrubs, with two species, of about 1⅓–2 m. It is the only genus in the family Roridulaceae. It has thin, woody, shyly branching, upright, initially brown, later grey stems, with lance- to awl-shaped leaves crowded at their tips. The star-symmetrical flowers consist from the outside in of five, green or reddish, free sepals, alternating with five white, pink or purple, free petals. Further to the middle and opposite the sepals are five stamens with the anthers initially kinked down. These suddenly flip up if the nectar-containing swelling at its base is being touched. The center of the flower is occupied by a superior ovary. The leaves and sepals carry many sticky tentacles of different sizes, that trap insects. Roridula does not break down the insect proteins, but bugs of the genus Pameridea prey on the trapped insects. These later deposit their feces on the leaves, which take up nutrients from the droppings. The species can be found in the Western Cape province of South Africa. They are commonly known as dewstick or fly bush in English and vlieëbos or vlieëbossie in Afrikaans.
Saxifraga flagellaris, the whiplash saxifrage or flagellate saxifrage, is a plant native all over the Eurasian Arctic Coast, Siberia, Far East, Caucasus and some areas of northern Rocky Mountains. It is not very common. It is also known as spider saxifrage or "spider plant", though the latter name more commonly refers to the unrelated Chlorophytum comosum (Agavaceae).
Saxifraga oppositifolia, the purple saxifrage or purple mountain saxifrage, is a species of plant that is very common in the high Arctic and also some high mountainous areas further south, including northern Britain, the Alps and the Rocky Mountains.
Micranthes stellaris, synonym Saxifraga stellaris, the starry saxifrage or hairy kidney-wort, is an Arctic–alpine species in the family Saxifragaceae. It produces panicles of 5–10 white flowers on a stem up to 20 cm (7.9 in) tall, rising from a basal leaf rosette. One subspecies is found from eastern Canada to Russia, including the British Isles, while another is found in the mountains of southern Europe.
A hydathode is a type of pore, commonly found in angiosperms, that secretes water through pores in the epidermis or leaf margin, typically at the tip of a marginal tooth or serration. Hydathodes occur in the leaves of submerged aquatic plants such as Ranunculus fluitans as well as herbaceous plants of drier habitats such as Campanula rotundifolia. They are connected to the plant vascular system by a vascular bundle. Hydathodes are commonly seen in water lettuce, water hyacinth, rose, balsam, and many other species.
Saxifraga paniculata is an alpine species of flowering plant in the saxifrage family, with native distribution in the temperate northern hemisphere. Common names include alpine saxifrage, encrusted saxifrage, lifelong saxifrage, lime-encrusted saxifrage, livelong saxifrage, white mountain saxifrage, and silver saxifrage.
Saxifraga stolonifera is a perennial flowering plant known by several common names, including creeping saxifrage, strawberry saxifrage, creeping rockfoil, Aaron's beard, mother of thousands, roving sailor, and strawberry begonia or strawberry geranium.
Central Europe contains several life zones, depending on location and elevation.
Saxifraga cuneifolia, the lesser Londonpride, shield-leaved saxifrage or spoon-leaved saxifrage, is a herbaceous perennial plant belonging to the Saxifragaceae family.
Saxifraga aspera is a species of saxifrage known by the common name of rough saxifrage. In German it is known as Rauhhaariger Steinbrech. It is placed in section Trachyphyllum of the genus Saxifraga. There are two subspecies, Saxifraga aspera subsp. aspera and Saxifraga aspera subsp. micrantha. It is a plant of the pan-Arctic tundra and is also found in Europe at moderately high altitudes in the Alps, Pyrenees and northern Apennines.
Saxifraga bryoides is a species of saxifrage known by the common name of mossy saxifrage. In German it is known as Moosartiger Steinbrech. It is an inhabitant of the Arctic tundra but it also grows in the Alps and other European mountain ranges at high altitudes.
Amorphous calcium carbonate (ACC) is the amorphous and least stable polymorph of calcium carbonate. ACC is extremely unstable under normal conditions and is found naturally in taxa as wide-ranging as sea urchins, corals, mollusks, and foraminifera. It is usually found as a monohydrate, holding the chemical formula CaCO3·H2O; however, it can also exist in a dehydrated state, CaCO3. ACC has been known to science for over 100 years when a non-diffraction pattern of calcium carbonate was discovered by Sturcke Herman, exhibiting its poorly-ordered nature.
Saxifraga rotundifolia, common name round-leaved saxifrage, is a flowering herb and alpine plant of the genus Saxifraga.
Saxifraga burseriana, called the early white-flowered saxifrage, is a species of flowering plant in the genus Saxifraga, native to the eastern Alps; Germany, Austria, Liechtenstein, Italy, and Slovenia. Its cultivar 'Crenata' has gained the Royal Horticultural Society's Award of Garden Merit.
Saxifraga paradoxa, commonly known as the fragile saxifrage, is a perennial plant species in the family Saxifragaceae, which occurs as a tertiary relict and endemic Saxifraga species in the South-Eastern Alps. Count Kaspar Maria von Sternberg described this species in his work Revisio Saxifragarum iconibus of 1810.
